guardrails-blindfold 0.1.0

Guardrails AI validator for PII detection and protection using Blindfold

Guardrails Blindfold

A Guardrails AI validator that detects and protects PII in LLM outputs using the Blindfold API.

Developed by	Blindfold
License	MIT
Input/Output	String
Hub	blindfold/pii_protection

Installation

pip install guardrails-blindfold

Set your Blindfold API key:

export BLINDFOLD_API_KEY=your-api-key

Get a free API key at app.blindfold.dev.

Quick Start

from guardrails import Guard
from guardrails_blindfold import BlindfoldPII

guard = Guard().use(BlindfoldPII(on_fail="fix"))

result = guard.validate("Contact John Doe at [e-mail]")
print(result.validated_output)
# → "Contact <Person_1> at <Email Address_1>"

Parameters

Parameter	Type	Default	Description
policy	str	"basic"	Detection policy — see table below
pii_method	str	"tokenize"	How to fix detected PII
region	str	None	"eu" or "us" for data residency
entities	list	None	Specific entity types to detect
score_threshold	float	None	Confidence threshold (0.0–1.0)
api_key	str	None	Falls back to BLINDFOLD_API_KEY env var
on_fail	str	None	Guardrails failure action

Policies

Policy	Entities	Use Case
basic	Names, emails, phones, locations	General PII protection
gdpr_eu	EU-specific: IBANs, addresses, dates of birth	GDPR compliance
hipaa_us	PHI: SSNs, MRNs, medical terms	HIPAA compliance
pci_dss	Card numbers, CVVs, expiry dates	PCI DSS compliance
strict	All entity types, lower threshold	Maximum detection

PII Methods

Method	Description	Reversible
tokenize	Replace with tokens (<Person_1>)	Yes
redact	Remove permanently ([REDACTED])	No
mask	Partially hide (J****oe)	No
hash	Deterministic hash (HASH_abc123)	No
synthesize	Replace with fake data (Jane Smith)	No
encrypt	AES-256 encryption	Yes (with key)

Examples

GDPR Compliance (EU Region)

guard = Guard().use(
    BlindfoldPII(
        policy="gdpr_eu",
        region="eu",
        on_fail="fix",
    )
)

result = guard.validate("Email [e-mail] about the meeting")
# → "Email <Email Address_1> about the meeting"

HIPAA — Redact PHI

guard = Guard().use(
    BlindfoldPII(
        policy="hipaa_us",
        pii_method="redact",
        region="us",
        on_fail="fix",
    )
)

result = guard.validate("Patient John Smith, SSN 123-45-6789")
# → "Patient [REDACTED], SSN [REDACTED]"

Block Output if PII Detected

guard = Guard().use(
    BlindfoldPII(policy="strict", on_fail="exception")
)

# Raises ValidationError if PII is found
result = guard.validate("No PII here")  # passes
result = guard.validate("Email [e-mail]")  # raises

Chain with Other Validators

from guardrails_blindfold import BlindfoldPII

guard = Guard().use(
    BlindfoldPII(policy="strict", on_fail="fix"),
).use(
    AnotherValidator(on_fail="exception"),
)

Detect Specific Entity Types

guard = Guard().use(
    BlindfoldPII(
        entities=["Email Address", "Phone Number"],
        on_fail="fix",
    )
)

Data Residency

Use the region parameter to ensure PII is processed in a specific jurisdiction:

• region="eu" — processed in Frankfurt, Germany
• region="us" — processed in Virginia, US

# EU data stays in the EU
guard = Guard().use(
    BlindfoldPII(policy="gdpr_eu", region="eu", on_fail="fix")
)

Links

• Blindfold Documentation
• Blindfold Dashboard
• Guardrails AI Documentation
• GitHub